Modular golf club

ABSTRACT

A modular golf club includes a head, a top shaft and a connector shaft between the head and the top shaft. The connector shaft has a couple of identical fastening means at both ends thereof. The fastening means is an insertion tip in the shape of regular hexagon and a union nut secured to the connector shaft slidably but with a limit defined by a radial flange at the base of the hexagonal tip. Either union nut has an inner thread toward its outer end the diameter of which is bigger than the flange to allow the union nut to be positioned over the hexagonal tip in a juxtaposed relationship.

BACKGROUND OF THE INVENTION

A. Field of the Invention

The present invention relates to golf clubs. More particularly the present invention relates to a modular golf club that enables golfers to carry less.

B. Description of the Prior Art

Golf is a game of precision played with a golf ball and a set of clubs on a grass course with a number of holes into which the ball must drop with preferably lesser stokes. Players seek to reduce stroke numbers and prefer to pick the best club for each stroke. Different clubs have different loft, distance and trajectories. The general caddieless players must carry all, fourteen or so clubs in a bulky golf bag about the course for hours.

Ideas of having a common club shaft share variety of head sections have been publicized. U.S. Pat. No. 6,547,673 to Roark incorporated herein by reference shows an interchangeable modular golf club head and adjustable handle system. Other U.S. Pat. Nos. 6,723,000 and 6,663,502 incorporated herein by reference also show interchangeable club heads. Unfortunately, because golf is a precision sport, the interchangeable system requires a firm connection. Because players cannot have unlimited time on the course, the interchange must also be quick and preferably without tools.

SUMMARY OF THE INVENTION

In view of the foregoing, it is an object of the present invention to provide a modular golf club, be it a putter, a wood, a wedge or an iron that provides an in-line and integral connection in a simpler way of sharing multiple golf heads. Another object of the present invention is to provide a modular golf club connection with virtually no addition of bulkiness or excess mechanism.

According to the present invention, a golf club comprises a head, a top shaft and a connector shaft between the head and the top shaft. The connector shaft has a couple of identical fastening means at both ends thereof. In one embodiment of the present invention, the fastening means is an insertion tip in the shape of regular hexagon and a union nut secured to the connector shaft slidably but with a limit defined by a radial flange at the base of the hexagonal tip. Either union nut has an inner thread toward its outer end the diameter of which is bigger than the flange to allow the union nut to be positioned over the hexagonal tip in a juxtaposed relationship.

To restrain the movement of the union nut on the connector shaft, the nut has its inner end an annular shoulder with a smaller diameter than that of the flange.

Identical receiving ends are provided distally at both the top shaft and the head units. Either receiving end is comprised of a hexagonal slot to receive and nonrotatably lock one of the hexagonal tips of the connector shaft and an outer thread which may be engaged with one of the union nuts to fasten the modular club members axially securely. Therefore, a speedy double fastening means is provided according to the present invention in order to interconnect the common golf shaft upper section and the various club heads such as a series of iron heads with high integrity.

The simplified intuitive method of the inventive golf club modules needs the golfers fasten one nut of the connector shaft to the top shaft section just once at a course and allows interchanges through the club lineup with turning the other nut one way or another on the selected club heads.

The present invention avoids to add the excessive contraptions to the conventional shaft profile only to make the replaceable club heads theoretically possible which will counteract the beneficial realization of having one common club shaft to master many golf heads explaining the reason behind no practical such clubs having been accepted with popularity yet.

Among others, a practical benefit of the present invention will be that no rattling along the entire length of the modular club should be concerned thanks to the unique structural feature requiring lesser components and giving more integrity to the resultant clubs.

Embodiments of the invention will now be described by way of example with reference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 a perspective view of the modular golf club according to the present invention.

FIG. 2 is an exploded perspective view of the component parts for a wood with the improved connection according to one embodiment of the invention.

FIG. 3 is a part-sectional front view of the club of FIG. 1 showing the club parts and mode of connections in detail.

FIG. 4 is a view of an alternate embodiment.

FIG. 5 is a view of an alternate embodiment.

Similar reference numbers denote corresponding features throughout the attached drawings.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

With reference to FIG. 1, a connector shaft 10 is shown in position between a top shaft 11 and a neck or hosel 12 of a club head 13, which is a replaceable wood with any one of irons, wedges, and a putter in the individual golfer's roster of clubs. The top shaft 11 has a typical design at its upper portion to have a general cylinder body topped with a grip and a cap not shown, as they are well known in the field. The lower end of the top shaft 11 is shaped to make the novel union with the connector shaft 10 through one of a couple of union nuts 14 and 14′. The golf club sections are locked in radial orientation around the shaft as well as longitudinal orientation that is parallel to the club shaft.

The wood head 13 as used for long-distance strokes by the golfer for tee shots has a longer predetermined neck or hosel than those of the irons, wedges, and putter for shorter-distance strokes in the respective specific circumstances of the course. So the wood is the longest club and iron, wedge and putter become shorter in this order. To keep the user operation as well as the manufacture of the inventive golf club modules intuitively simple, the top shaft 11 and then its assembly with the connector shaft 10 remains a common component of the golf club. Even the neck or hosel 12 of the head 13 is terminated with an identical shape to that of the lower end of the top shaft 11 to make another novel union with the union nut 14 or 14′.

For example, the top shaft 11 may be nineteen inches long and the connector may be seventeen inches to make a thirty six inch shaft of an iron. The variation requirements between the irons and other types of clubs then can be met by varied neck lengths specified for the respective club heads which can be realized by the current manufacturing facilities. The connection thus has means preventing the twisting of the shaft as well as the bending of the shaft as well as pulling of the shaft away from the club head. This is shown in the following drawings.

Referring now to the connector shaft 10 shown in FIGS. 2 and 3, it is clear how shaft 10 can interconnect the top shaft 11 and the club head 13. The shaft 10 works as a lower extension of the top shaft 11 while serving its connection duty with the head 13. The shaft 10 is comprised of a body 110 which is generally cylindrical but its opposite ends formed with a couple of identical hexagonal tips 15 and 15′. The hexagonal tips 15 and 15′ have converging points 16 and 16′ for insertions to the top shaft 11 and the neck or hosel 12, respectively. To receive the tips 15 axially into the shaft 11, it has a blind opening or corresponding hexagonal slot 17 into which the point 16 leads the tip 15 into non-rotatable locking engagements between the shafts 11 and 10. The converging point 16 forms a face 160 preventing bending motion. The convergent tip and face should be long enough to prevent mending motion.

A radial flange 18 is provided at the base of the hexagonal tip 15 acting as a stop abutting the bottom of the shaft 11. Radially outward of the slot 17 is formed a threaded end 19 on the shaft 11 to allow a secondary locking means to achieve rigidity in the connection of the modular golf club. A couple of union nuts 20 and 20′ formed as internally threaded collars are slidably attached on the cylindrical body 110. Union nuts 20 and 20′ have identical structure wherein a nut 20 has an inner thread 120 at its open end toward the corresponding tip 15 of the shaft 10 and at its opposite end an annular shoulder 121 with an inner diameter to slide up and down over the outer diameter of the body 110. However, the nut 20 is limited to slide up to the flange 18 where it stops in a juxtaposed relationship to each other while the identical nut 20′ is slid down to the flange 18′ into the similar limited position. The shoulder 121 has its inner diameter set so that it slides on the body 110 between the opposite flanges 18 and 18′.

The body may be made of a metal pipe cut to length which is then plugged by end pieces of the tips 15 and 15′ formed with flanges 18 and 18′ having two opposing union nuts 20 and 20′ fitted thereon as is depicted on the drawings.

Also, the cylindrical body 110 and the tips 15 and 15′ with flanges 18 and 18′ may be a solid one piece made of a light weight material with an appropriate surface finish and the union nuts 20 and 20′ may either be metal or plastic components which can be subsequently assembled onto the body 110 according to the present invention. In this case, the nuts 20 and 20′ can be machine pressed onto the body 110 over the flanges 18 and 18′, which will then limit the nut movement therebetween.

In taking such construction of golf club modules of the present invention out to the course, the top shaft 11 may be carried with the connector shaft 10 in a light weight bag for field assembly into an integral shaft component using the union nut 20 leaving the other nut 20′ free for mating with the golfer's choice of head. Depending on the distance to cover and the particular situation, players choose a club with the appropriate characteristics. Choosing a club will be as fast as interchanging the desired heads with the complement of tightening one nut 20′ over the club head of choice. Except the only sliding part of the nut 20′ that will be screw tightened on the head 12, there are provided no parts to move or rattle even under excessive force of hit or mishit throughout the club of the present invention.

Because the differentiation in club length has been built into the neck sizing in the respective heads, only the nut 20′ is left to handle at the golfer's end to achieve the high speed and integrity of the modular golf club through the connector shaft of the present invention.

The nut 20 is shown as a smooth circular profile cylindrical member, but can also have at least one of a thumb and/or forefinger protrusions as in a win nut allowing easy hand tightening. The protrusions or protrusion can be made detachable. The nut 20 formed as a collar is preferably made of metal allowing secure connection between the shaft and head preventing pulling of the shaft away from the head during ball striking. The nut 20 can also be formed as a hexagonal profile allowing a wrench tool for changing club head and shaft. Although a hexagonal protrusion is preferred, any non-circular cross section protrusion can be used.

FIG. 4 shows an alternate embodiment where the shaft 11 is directly connected to the protrusion 15 that is connected to the slot 17. The connection means is analogous to the primary embodiment where the collar nut 14 secures over the threaded portion 19. Having a single connection is better than having the double connection because it decreases complexity, cost and chance for malfunctions during ball striking. The alternate embodiment would not allow a variety of different shafts having varying lengths and characteristics. In the primary embodiment as shown in figure two, the shaft 110 can be made in a variety of different characteristics, varying in flexibility, lengths, weight and color. Also, the primary embodiment has the benefit of different styles of grips that can be interchanged without changing the shaft.

FIG. 5 shows an alternate embodiment where the connection means is reversed. In this case, the hosel 12 has a protrusion 15 and the shaft has a slot receiving the protrusion 15.

It is to be understood that the present invention is not limited to the sole embodiment describe above, but encompasses any and all embodiments within the scope of the following claims. One of the equivalent connection means is reversing the connection at the club head and shaft so that the club head provides a non-circular protrusion and nut engaging with a shaft having a hole adapted for the non-circular protrusion and having thread allowing the nut to be attached. 

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 8. A modular golf club comprising: a shaft section having a top grip at a top end, and a protrusion having a noncircular cross section protruding from the bottom end, an internally threaded collar nut rotably mounted in a common axial position to the shaft section, a plurality of clubheads, each having a slot for snugly receiving the protrusion and each having an external thread for receiving the internally threaded collar nut, wherein the protrusion does not rotate relative to the slot when inserted in the slot.
 9. The modular golf club of claim 8, wherein the protrusion has a pointed flathead tip for insertion into the slot, wherein the slot is shaped to receive the flathead tip.
 10. The modular golf club of claim 8, further comprising a radial flange at a base of the protrusion, wherein the protrusion can be inserted into the slot until the flange abuts the shaft, whereby the internally threaded collar nut can be tightened to complete axial and radial connection.
 11. The modular golf club of claim 10, wherein the slot shaped as a regular hexagon and the protrusion is a similarly sized regular hexagon.
 12. The modular golf club of claim 10, wherein the protrusion terminates in a flat head and the slot is shaped to receive the protrusion.
 13. The modular golf club of claim 1, wherein the club lengths vary due to varying hosel length.
 14. A modular golf club comprising: a selection of clubheads, each having a protrusion having a noncircular cross section protruding from the hosel, an internally threaded collar nut rotably mounted in a common axial position to the hosel, a shaft section having a top grip at a top end, and at a bottom end, a slot for snugly receiving the protrusion, wherein the bottom end has an external thread for receiving the internally threaded collar nut.
 15. The modular golf club of claim 14, wherein the protrusion has a pointed tip for insertion into the slot, wherein the slot is shaped to receive the pointed tip.
 16. The modular golf club of claim 15, further comprising a radial flange at a base of the protrusion, wherein the protrusion can be inserted into the slot until the flange abuts the shaft, whereby the internally threaded collar nut can be tightened to complete axial and radial connection so that the golf club is locked in radial orientation as well as longitudinal orientation.
 17. The modular golf club of claim 14, wherein the slot is shaped as a regular hexagon and the protrusion is a similarly sized regular hexagon.
 18. The modular golf club of claim 14, wherein the protrusion terminates in a pointed flat head tip and the slot is shaped to receive the protrusion. 